Question

I have been walking through an xsl document and am not sure what the @domain$ne$ stands for. Can you please help?

 <xsl:for-each select="./HEADER/META
                          [(./VALUE[not(text()='')]) and
                           (./@domain$ne$'PPPI_PROCESS_ORDER') and
                           (./@domain$ne$'PPPI_PROCESS_ORDER_TEXT') and
                           (./@domain$ne$'PPPI_MATERIAL') and 
                           (./@domain$ne$'PPPI_MATERIAL_SHORT_TEXT')]"

Answer 1

As others have pointed out, that is not valid XPath (or XSLT).

However in XPath 2.0 there is a ne operator, meaning “not equals”. It’s like != but applies to single, atomic values instead of node sets (existential comparison).

It looks very likely that ne is what’s intended, but the $ signs should be replaced with spaces.

<xsl:for-each select="./HEADER/META
                      [(./VALUE[not(text()='')]) and
                       (./@domain ne 'PPPI_PROCESS_ORDER') and
                       (./@domain ne 'PPPI_PROCESS_ORDER_TEXT') and
                       (./@domain ne 'PPPI_MATERIAL') and 
                       (./@domain ne 'PPPI_MATERIAL_SHORT_TEXT')]">

I wonder what happened to it that the nes got surrounded with $.

There are a few other things you could do to make the code less verbose, but that’s not the focus of your question.